The present invention relates to a dredger comprising a floating body, a boom which extends forwardly and carries at its front end a disintegrating tool, the said boom being pivoted by its rear end on the floating body in such a manner as to be able to assume either a working position, in which it is dipped to a greater or lesser extent, or a raised position of rest, and further comprising suspension means for the boom enabling its position to be adjusted.
With dredgers of this kind it is usually the displacement of the floating body itself by means of piles and cables, known as swinging cables, associated with winches and having their ends anchored in the sea-bed, that makes it possible to dredge in an arc of a circle.
When it is desired to dredge in ports it is therefore necessary to remove the ships which would hinder this work. This evacuation is onerous and adds considerably to the cost of the dredging operation.
Another disadvantage of known dredgers of the kind indicated above is that they lack stability and efficiency when they are required to dredge a hard bed or to excavate rocks, because of their instability caused by reaction forces resulting from the action of the tool.
The present invention relates to a dredger which is exempt from these various disadvantages and which permits dredging with a large radius of action under floating obstacles, which need not be removed, while in addition this dredger permits excavation of rocks as well as dredging of soft or semi-hard beds, while it is of simple and strong construction.